This application relates generally to apparatus and methods for detecting the presence of and/or measuring analytes of interest by inducing and detecting electrochemiluminescence in a test sample.
Numerous methods and systems have been developed for the detection and quantitation of analytes of interest in biochemical and biological substances. Methods and systems which are capable of measuring trace amounts of microorganisms, pharmaceuticals, hormones, viruses, antibodies, nucleic acids and other proteins are of substantial value to researchers and clinicians.
Chemiluminescent assay techniques have been adopted in which a sample containing an analyte of interest is mixed with a reactant labeled with chemiluminescent label. The reactive mixture is incubated and some portion of the labeled reactant binds to the analyte. After incubation, the bound and unbound fractions of the mixture are separated and the concentration of the label in either or both fractions can be determined by chemiluminescent techniques. The level of chemiluminescence determined in one or both fractions indicates the amount of the analyte of interest in the sample. Electrochemiluminescent (ECL) assay techniques provide improvements over chemiluminescent techniques. They provide a sensitive and precise measurement of the presence and concentration of an analyte of interest. In ECL techniques the incubated sample is exposed to a voltammetric working electrode in order to trigger luminescence. In the proper chemical environment, such electrochemiluminescence is triggered by a voltage impressed on the working electrode at a particular time and in a particular manner. Light produced by an electrochemiluminescent label is measured to provide an indication of the presence of the analyte or to measure the same.
While ECL techniques have been developed for use in the laboratory, there is a need for a practical ECL instrument capable of carrying out multiple assays in an efficient and reproducible manner.